226 SCIENTIFIC AND APPLIED PHARMACOGNOSY 



A _^-^^-?=^=^=^=> F. \ V^ ^ -r \ D 



End 



H 



FIG. 99. Coptis. A, transverse section of peripheral portion of a stretched 

 internode in the rhizome; Ep, epidermis; C, cortex. B, transverse section 

 of rhizome: C, cortex; End, endodermis; P, pericycle; L, leptome; H, 

 the xylem or vessels. C, section of same internode as in A and B showing 

 the libriform or wood fibers (H) between the two arches of collateral mestome- 

 bundles. D, transverse section of a root; Ep, epidermis; Ex, exodermis; 

 C, cortex; End, endodermis; P, pericycle; L, leptome; H, hadrome. E, 

 transverse section of a leaflet: Ep, the epidermal cells of the ventral surface; 

 Ed, epidermal cells of the lower or dorsal surface; P, palisade cells; Pn, 

 loose mesophyll or dorsal pneumatic tissue; St, stereome on the leptome- 



